^ What if the tags you talked about were treated as a group?

That is [male/female anthro feral duo] would be treated like a single tag, [female solo feral] would be treated like a single tag. A picture would either match all of the tags in a given group and be suggested, or not fully match any group and be rejected.

To me that seems to express what you actually want.

(although the solo/duo/group thing may be a bit fuzzy due to inadequate tagging..)